Quantitative gait analysis is essential for understanding motor function and guiding clinical decisions. While marker-based motion capture (MoCap) systems are accurate, they are costly and require specialized facilities. OpenCap, a markerless alternative, offers a more accessible approach; however, its reliability across different walking speeds remains uncertain. This study assessed the agreement between OpenCap and MoCap in measuring spatiotemporal parameters, joint kinematics, and center of mass (CoM) displacement during level walking at three speeds: slow, self-selected, and fast. Fifteen healthy adults performed multiple trials simultaneously, recorded by both systems. Agreement was analyzed using intraclass correlation coefficients (ICC), minimal detectable change (MDC), Bland–Altman analyses, root mean square error (RMSE), Statistical Parametric Mapping (SPM), and repeated-measures ANOVA. Results indicated excellent agreement for spatiotemporal variables (ICC ≥ 0.95) and high consistency for joint waveforms (RMSE < 2°) and CoM displacement (RMSE < 6 mm) across all speeds. However, the joint range of motion (ROM) showed lower reliability, especially at the hip and ankle, at higher speeds. ANOVA revealed no significant System × Speed interactions for most variables, though a significant effect of speed was noted, with OpenCap underestimating walking speed more at fast speeds. Overall, OpenCap is a valuable tool for gait assessment, very accurate for spatiotemporal data and CoM displacement. Still, caution should be taken when interpreting joint kinematics and speed at different walking speeds.

The COVID-19 pandemic may be having many psychological impacts on people, at both an individual and a community level. To ascertain the relationship between the weekly frequency of physical activity and levels of stress among Brazilian adults during social distancing due to the coronavirus (COVID-19), and the interaction of sex in this association. Cross-sectional study with a descriptive approach conducted at a public university in Curitiba (PR), Brazil. 2,000 Brazilian adults (average age 36.4 years; 59.6% women) were recruited according to convenience through digital media. They filled out a questionnaire in electronic format that asked for sociodemographic information, health data, food consumption data, weekly frequency of physical activity and stress levels on the 10-item Kessler psychological distress scale. Descriptive statistics and regression analyses were used to evaluate the data. Associations were observed for the following correlations: male sex * no physical activity (odds ratio (OR): 4.35; 95% confidence interval (CI): 1.14-16.67); female sex * physical activity 4 or 5 times a week (OR: 7.86; 95% CI: 2.28-27.05); female sex * physical activity 3 times a week (OR: 7.32; 95% CI: 2.09-25.58); female sex * physical activity 1 or 2 times a week (OR: 14.57; 95% CI: 4.28-49.57); and female sex * no physical activity (OR: 24.17; 95% CI: 7.21-80.97). The lower the weekly frequency of physical activity during the period of social distancing was, the greater the chances of having stress levels were, especially for women.

Background: Gait analysis plays a key role in detecting and monitoring neurological, musculoskeletal, and orthopedic impairments. While marker-based motion capture (MoCap) systems are the gold standard, their cost and complexity limit routine use. Recent advances in computer vision have enabled markerless smartphone-based approaches. OpenCap, an open-source platform for 3D motion analysis, offers a potentially accessible alternative. This review summarizes current evidence on its accuracy, limitations, and clinical applicability in gait assessment. Methods: A search was performed in major scientific databases to identify studies published from OpenCap’s release in 2023 to June 2025. Articles were included if they applied OpenCap to human gait and reported quantitative biomechanical outcomes. Both validation and applied studies were considered, and findings were synthesized qualitatively. Results: Nine studies were included. Validation research showed OpenCap achieved generally acceptable accuracy kinematics (RMSE 4–6°) in healthy gait, while increased errors were reported for pathological gait patterns. Applied studies confirmed feasibility in different clinical conditions, though trial-to-trial variability remained higher than MoCap, and test–retest reliability was moderate, with minimal detectable changes often exceeding 5°, limiting sensitivity to subtle clinical differences. Conclusions: OpenCap is a promising, low-cost tool for gait screening, remote monitoring, and tele-rehabilitation. Its strengths lie in accessibility and feasibility outside laboratory settings, but limitations in multiplanar accuracy, pathological gait assessment, and kinetic estimation currently preclude its replacement of MoCap in advanced clinical applications. Further research should refine algorithms and standardize protocols to improve robustness and clinical utility.

Firefighting requires a high level of physical fitness and causes substantial psychological stress, engendering musculoskeletal, mental, and cardiac issues. Consequently, it is necessary to measure the preparation of the firefighters daily through the Firefighting Physical Ability Tests (FPATs). According to the literature, some variables are more important for performance in the FPAT. Therefore, we aimed to summarize evidence that relates physical and mental aspects to the FPAT performance. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) method, screening 1055 records from databases and selecting 15 that met inclusion criteria. No emotional and psychological variables were correlated with the FPAT. Most research shows significant correlations between the FPAT performance and the following: aerobic fitness, upper body endurance and strength, anaerobic capacity, body fat, and age. Lower body endurance and strength, as well as anaerobic power, had a low number of investigations and need to be further explored. Abdominal endurance showed weak correlations, while flexibility did not show any correlations in most studies, although these should be considered for injury prevention. We recommend that fitness programs and evaluations include a global analysis considering the evidence presented for methodological improvements.